Abstract: A video controller for controlling at least two video displays incorporates a video memory for storing first and second video frames of interleaved pixel data. A video memory controller connected to the video memory sequentially reads data for a first pixel from the first video frame and data for a second pixel from the second video frame. Each pixel data is in turn transferred to a look-up table connected to the video memory controller which converts the first and second pixel data to first and second display data. A selector coupled to the look-up table alternately routes the first display data to one video display and routes the second display data to the other video display.

Abstract: An image displayed on a digital display such as a flat panel display is rotated while the same image is displayed on a cathode ray tube display in unrotated form. When image rotation is selected, the read address sequence into a frame buffer may be reversed and the bit read sequence may be reversed. Thus a frame of panel pixel data stored within the frame buffer of an external video memory may be scanned onto a flat panel to display a rotated image.

Abstract: A display system in a computer or multimedia system maintains a predetermined image quality. The display system includes an intelligent display driver controller (IDDC), a serial PROM, display screen, and sensors. The IDDC controls display of input image data on the display screen based on a control set. The serial PROM stores a plurality of such control sets, each of which has a predetermined effect on the image quality. The sensor measures a parameter, a change in which may degrade the image quality on the display screen. In response to such a change, the IDDC retrieves a new control set from the serial PROM, and controls display of input image data based on the new control set retrieved. As a result, the IDDC maintains the predetermined image quality on the display system independent of change in the measured parameter.

Abstract: A digital system provides command data to a display system during the display time period such that minimal image degradation occurs. The digital system includes a CPU coupled to a graphics controller coupled to a display system via a cable. The display system includes an intelligent display driver controller (IDDC), driver circuits, display screen, and possibly sensors. The IDDC operates on image data and instructs the driver circuits to display an image on the display screen. Operating condition changes measured by transducers may result in a degradation in image quality unless a response is made. The digital system may automatically respond to operating condition changes to maintain a predetermined image quality level. Alternatively a user's request may change the image quality. In either case the CPU is interrupted and it provides one or more control sets of command data interspersed within the image data transparently to the graphics controller.

Abstract: The system provides for vertical or horizontal centering, or both, without the use of a memory frame buffer, of raster image data whose start time and duration cannot be controlled. The centering is accomplished by controlling the frame start time and line start time of the overall display of the raster imaging surface. This is accomplished in the case of vertical centering by detecting the time of the beginning of the first or last line, or both, of the total lines of the raster image data to be displayed an controlling the start time of a subsequent one of the frames based on that detected time. Horizontal centering is carried out by detecting the time of the beginning of the first or last column, or both, of the columns in one or more of the lines of the raster image data and controlling the start time of subsequent ones of the lines based on that detected time.

Abstract: The perception of grayscale shading on a digitally commanded display is produced by commanding pixels of the display with brightness-setting signals of differing average duty cycles. Brightness-setting signals having one brightness level associated with them are phase shifted in relation to time and distributed to spaced apart pixel locations at which the one brightness level is to be produced. The energization of spatially adjacent pixels is scattered in time and pixels which are energized at the same time are selected to be spatially scattered so as to avoid the perception of visual disturbances such as flickering and surface streaming.

Abstract: The system provides for vertical or horizontal centering, or both, without the use of a memory frame buffer, of raster image data whose start time and duration cannot be controlled. The centering is accomplished by controlling the frame start time and line start time of the overall display of the raster imaging surface. This is accomplished in the case of vertical centering by detecting the time of the beginning of the first or last line, or both, of the total lines of the raster image data to be displayed and controlling the start time of a subsequent one of the frames based on that detected time. Horizontal centering is carried out by detecting the time of the beginning of the first or last column, or both, of the columns in one or more of the lines of the raster image data and controlling the start time of subsequent ones of the lines based on that detected time.

Abstract: The perception of grayscale shading on a digitally commanded display is produced by commanding pixels of the display with brightness-setting signals of differing average duty cycles. Brightness-setting signals having one brightness level associated with them are phase shifted in relation to time and distributed to spaced apart pixel locations at which the one brightness level is to be produced. The energization of spatially adjacent pixels is scattered in time and pixels which are energized at the same time are selected to be spatially scattered so as to avoid the perception of visual disturbances such as flickering and surface streaming.